feat: add Docker build

main.go

@@ -65,9 +65,15 @@ func main() {
 
 	// Initialize MQTT client if enabled
 	var mqttClient *mqtt.MQTTClient
-	if *mqttServer != "" {
-		log.WithField("server", *mqttServer).Info("Initializing MQTT client")
-		mqttClient = mqtt.NewMQTTClientFromEnv(*mqttServer)
+	// Check for MQTT server from flag or environment variable
+	mqttServerURL := *mqttServer
+	if mqttServerURL == "" {
+		mqttServerURL = os.Getenv("MQTT_SERVER")
+	}
+
+	if mqttServerURL != "" {
+		log.WithField("server", mqttServerURL).Info("Initializing MQTT client")
+		mqttClient = mqtt.NewMQTTClientFromEnv(mqttServerURL)
 
 		// Set callback to forward MQTT messages to WebSocket
 		mqttClient.SetMessageCallback(func(topic string, data []byte) {